Electrical conductor for oil-tanks



(No Model.)

I I H. W. SPANG. ELECTRICAL CONDUCTOR FOR OIL TANKS.

No. 286,086. Patented Oct. 2, 1883.

q 6 E m L /L L l M i i M w E C I A a 4 o X WITNESSES INVENTOR F v H 1 0 1 By his flltorneys 0U? Pa)? UNITED STATES PATENT OFFICE.

HENRY W. SPANG, OF READING, PENNSYLVANIA.

ELECTRICAL CONDUCTOR- FOR OIL-TANKS.

SPECIFICATION forming part /of Letters Patent No. 286,086, dated October 2, 1883.

Application tiled August 1853.

El) all whom it may concern.-

Be' it known that I, HENRY XV. SPANG, a citizen of the United States, residing at Reading, in the county of Berks and State of Pennsylvania, have invented certain new and useful Improvements in Electrical Conductors for Oil-Tanks, of which the following is a specification.

The object of my invention is to apply such a system of conductors to metallic tanks used for the storage of petroleum or other inflammable liquids as shall afford the electricity of a lightning discharge a path to and from the earth in such manner as will prevent the occurrence of disruptive discharges in the immediate neighborhood of the tank, and to combine with such a system means for preventing the escape of gases from the tank in the neighborhood of the conductors, thereby precluding the possibility of ignition of the contents of the tank by flame communicated by the combustion of such gases.

The invention consists in inclosing a tank in a system of conductors radiating from one or more points above the tank, and respectively extending to earth terminals placed at suitable distances from the base of the tank. This system of conductors is electrically connected with the metallic supply and delivery pipes passing to and from the tank, and also at convenient points with the tank itself. As it is essential, however, that the gas which is constantly forming in the tanks should be prevented from escaping in the neighborhood of the conductors, I combine with this system a pipe constructed of electrically non-conducting material leading from the upper part of the tank to a suitable and safe distance therefrom. Through this pipe the gas is permitted to escape from the tank.

In the accompanying drawings, Figure lis an elevation of a tank equipped with a system of conductors and a gas-pipe, illustrating my invention; and Fig. 2 is a plan view of the same.

Referring to the drawings, A represents an oil, tank of well-known construction, and E and F represent the metallic supply and delivery pipes, respectively.

From the upper portion of the tank extends a rod, ll, of iron or other conducting (No model.)

material, for supporting the upper extremities of a radial system of conductors, J J, &c. The conductors J are secured to a ring or plate, I, fastened to the rod H a short distance from its upper extremity. The lower extremities of the conductors J are preferably secured to metallic earth terminals K, placed at equal distances from each other about the base of the tank A. The earth terminals K,which I prefer to employ, consist of perforated metallic tubes,constructed in a manner fully described in a patent issued to me on the 7th day of September, 1875, N 0. 157,415. The conductors J are also electrically connected with the tank A at convenient points L, for the purpose of placing the tank itself in electrical connection with the entire system of conductors, thereby preventing the formation of electric arcs between the conductors and the tank. The pipes E and F are also placed in electrical connection with the system of conductors J, as shown at M and N, respectively. This connection is of especial importance, in that it materially enlarges the area through which the electricity is collected and dispersed.

Upon the upper portion of the tank A is formed a dome, G, for collecting the gas which forms within the tank. A tube or pipe, 0, leads from this domev G to a distance from the tank, and serves to conduct the gas away from the tank to such a distance as may be found desirable. The tube 0 is of non-conducting material, and therefore cannot under any circumstances convey electricity to and from the tank. In this manner the ignition of the gas in the immediate vicinity of the tank, which is the chief danger experienced in a thunderstorm, is effectually prevented.

I claim as my invention-.-

1. The combination, substantially as hereinbefore set forth, of the metallic tank and its supply and discharge pipes, a radial system of electrical conductors surrounding said tank an d in electrical connection with the same, independent conductors connecting said supply and discharge pipes directly with the last named conductors, and a series of earth terminals with which said series oi conductors are electrically connected.

2. The combination, substantially ashereinbefore set forth, of themetallic tank, its supply and discharge pipes a radial system of of electric conductors surrounding said tank, electrical conductors surrounding said tank, and a non-conducting gas-escape tube leading and inelectrical connection with the same and from said tank. with said supply and discharge pipes, a series In testimony whereof I have hereunto sub- 5 of earth terminals With'which said conductscribed my name this 28th day of July, A. l). I 5

01s are electrically connected, and an inde- 18S3 pendent gas-escape tube of non-conducting HENRY \V. SPANG. material leading from said tank. lVitnesses:

3. The combination, substantially asherein- O. 'HoLToN, IMO before setforth, of the metallic tank,a system v Isaac Y. SPANG. 

